This application is a continuation-in-part of co-pending application Ser. No. 170,380 filed Mar. 18, 1988 entitled Single Line Compatible Fax System by the common inventor of this application, the teachings of which are incorporated herein by reference.
The present invention relates to telephone and facsimile systems and, more particularly, to telephone apparatus for answering an incoming call over a single telephone line and for automatically switching the call from the telephone to a facsimile machine connected thereto in response to an incoming facsimile call.
Facsimile (FAX) machines are rapidly growing in popularity as they become cheaper and cheaper. One of the target groups for future development and sales is the so-called "low end user", e.g. home offices, small businesses, and individuals for personal and business use. In instances where the user does not wish to install a separate telephone line for the FAX machine, the prior art offers no satisfactory options. The telephone and FAX machine can be connected to a single telephone line through a Y-connector which places the two devices in parallel. Outgoing use of either the telephone or FAX machine is easy with this arrangement; however, the FAX machine, being automatic in its operation when turned on, will tend to grab all the incoming calls. For that reason, the telephone and FAX machine are more commonly connected to a single telephone line through a switch which allows the user to select which of the devices is connected to the common telephone line at any time. When the user wants to use the FAX machine (and at night when unattended), it is switched to the telephone line. The rest of the time, the telephone is connected through the switch. As can be appreciated, this arrangement has many shortcomings as well. If one wants to receive incoming FAX transmissions when out of the office, it is imppossible to have a telephone answering machine to receive incoming telephone calls. Moreover, during the daytime when the office is attended and the switch has the telephone connected to the telephone line, anyone wishing to send a FAX transmission must first call on the telephone and advise the user to switch to the FAX position.
In my above-referenced co-pending patent application, I disclosed a method and apparatus for permitting a telephone and FAX machine to share a common telephone line. In one embodiment therein, there is switching circuitry that accomplishes the testing of the incoming call and the switching thereof to the telephone or FAX machine as appropriate. An incorporation of the switching circuitry into an answering machine is also described. Further, a method and apparatus for having the switching circuitry control a plurality of telephones is also shown.
It is the object of the present invention to provide a master telephone incorporating the above-mentioned switching and multiple telephone control functions into a master telephone which can be plugged into a telephone outlet to thereby control the balance of the telephones connected to the line and a FAX machine plugged into the master telephone.
Other objects and advantages of the present invention will become apparent from the description which follows hereinafter when taken in conjunction with the drawing figures which accompany it.